I have an old XP PC & a Samsung S3 Mini. I'm currently on Thunderbird 45.0 & Birdiesync 3.0.1.1.

I have 2 wifi sources in my house, one Plusnet box upstairs & one TP-Link downstairs. For some time I have only been able to sync through the downstairs link. Upstairs says the phone is connected, but no sync occurs. Today I find I can't sync downstairs either. The phone says it's connected, but Birdiesync says there's only a single source connected, so nothing to sync! The configuration window says "Source config is disabled during the connection with source GT-18190N"(the phone), which to me suggests it thinks it is connected! It worked fine a couple of days ago. I haven't changed anything.

I'm having the same problem. I can connect my android phone to the server (only by giving the IP address) and the phone says "connected to host ....", but the phone doesn't appear in the list of connected sources on the server. I tried creating rules for incoming/outgoing connections in the firewall, and I also deactivated the firewall, but still the server doesn't show the phone.

Which BirdieSync version is installed on your PC (BirdieSync menu Help/About...) ? Is it a 3.0 version ?
If yes, can you confirm that option "BirdieSync server 2.x" is unchecked in BirdieSync app Settings on your mobile device ?

Can you plug you Android device via USB, then build a log archive with BirdieSync menu "Help/Archive logs...", then send BirdieSyncLog.zip to support(at)birdiesync.com ?

Thanks for your reply.
The problem was that my mobile app was version 2.x.x.x. Thanks to your questions I discovered that I didn't have the option to disable BirdieSync ver 2, and installed the new one that works well with both WiFi and Bluetooth.